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1. What is the rule of rare event?
2. How to use rule of rare event to do hypothesis testing?
3. Why the p-value method and the rejection region method gave you the same conclusion in
hypothesis testing?
4. What is the major difference between the p-value method and the rejection region method?
5. For constructing confidence intervals for the population mean, what formulas do we have? How to
decide which formula to use?
6. When performing hypothesis testing for the population mean, how to set up the problem in symbolic
form? How to decide the H-null hypothesis? How to decide the type of the test?
7. How to decide the test is based on normal distribution or t distribution?
8. How to decide the p-values for the three types of test for the population mean?
9. How to find out the rejection regions for the three types of test?
10. The crown Bottling Company has just installed a new bottling process that will fill 16-ounce bottles
of the popular Crown Classic Cola soft drink. Both overfilling and underfilling bottles are undesirable. In
order to verify that the filler is set up correctly, the company wishes to see whether that mean bottle fill,
µ, is close to the target fill of 16 ounces. To this end, a random sample of 36 filled bottles is selected
from the output of a test filler run with mean 16.02. Let significance level be 0.01. Assume population
standard deviation is 1. If the sample results cast a substantial amount of doubt on the hypothesis that
the mean bottle fill is the desired 16 ounces, then the filler’s initial setup will be readjusted.
Please use both p-value method and rejection region method to solve the problem.
11. “Very satisfied” customers give the XYZ-Box video game system a rating that is at least 42. Suppose
that the manufacturer of the XYX-Box wishes to use the random sample of 65 satisfaction ratings to
provide evidence supporting the claim that the mean satisfaction rating for XYZ-Box exceeds 42. The
mean of the sample is 42.954. Population sigma is 2.64. Significance level is 0.01.
Please use both p-value method and rejection region method to solve the problem. Interpret your
result.
12. A microwave oven repairer says that the mean repair cost for damaged microwave ovens is less than
$90. You work for the repairer to test this claim. You find that a random sample of five microwave ovens
has a mean repair cost of $73 and a standard deviation of $11.50. At α=0.01, do you have enough
evidence to support the repairer’s claim? Assume the population is normally distributed.
13. You randomly select 16 coffee shops and measure the temperature of the coffee sold at each. The
sample mean temperature is 162.0 with a sample standard deviation of 10.0. Assume the temperatures
are normally distributed. Determine the sample size needed to make us 99% confident that the sample
mean is within a margin of error of 0.5 degree of mu.
14. A real estate agency collects data concerning y=the sales price of a house (in thousands of dollars),
and x=the home size (in hundreds of square feet). The data are given in the file RealEst.
From the Excel output find out r and decide if there is linear correlation between x an y; find out the
coefficient of determination and interpret it; write the least squares prediction equation; interpret the
meaning of b1; predict the mean sales price of all houses having 3 hundred square feet.
SUMMARY OUTPUT
Regression Statistics
Multiple R
0.937858
R Square
0.879578
Adjusted R
Square
0.864526
Standard
Error
10.58797
Observation
s
10
ANOVA
df
SS
Regression
1
6550.668
Residual
Total
8
9
896.841
7447.509
Coefficien
ts
Standard
Error
48.0244
14.41355
5.700298
0.745706
Intercept
X Variable 1
MS
6550.66
8
112.105
1
F
58.4332
6
t Stat
3.33189
3
7.64416
5
P-value
0.01035
5
6.05E05
Significan
ce F
6.05E-05
Lower
95%
14.7867
3.980697
Upper
95%
81.2621
1
7.41989
8
Lower
95.0%
14.7867
3.98069
7
Upper
95.0%
81.2621
1
7.41989
8